Thermostatic circuit closer



June 20, 1939. o. A. SAHLBOM 2,152,974

THEROSTATIC CIRCUIT CLOSER Filed Jan. 4, 1938 Inventor '4 J'a/zzom M Attorneys Patented June 20, 1939 UNITED STATEE ATENT OEFIQE 1 Claim.

This invention relates to a thermostatic circuit closer, the general object of the invention being to provide a container having mercury therein, with means for closing a circuit when the mercury rises in the container to a certain position therein.

This invention also consists in certain other features of construction and in the combination and arrangement of several parts, to be hereinafter fully described, illustrated in the accompanying drawing and specifically pointed out in the appended claim.

In describing the invention in detail, reference will be had to the accompanying drawing wherein like characters denote like or corresponding parts throughout the several views, and in which:

'igure l is a front View of the device.

Figure 2 is a longitudinal sectional through the body of the device.

Figure 3 is a view of the plug of non-conductive material, with the plug in inverted position.

Figure 4 is a section on the line 4-4 of Figure 2.

Figure 5 is a section on the line 55 of Figure 2.

In these views the numeral l indicates a plug or body of non-conductive material and having a bore 2 therein, the lower end of which is enlarged as shown at 3 and the upper end of the bore terminates an appreciable distance from the upper end of the plug and a transverse hole 6 in the plug communicates with the said upper end of the bore and the outer ends of the hole connect with the grooves l in the sides of the plug, said grooves extending from the hole through the upper end of the plug. A lower metal cap 8 fits over the lower part of the plug and an upper metal cap 9 fits over the upper portion thereof. The lower end of the lower cap 8 is spaced from the lower end of the plug and forms a chamber for receiving mercury and when this mercury exview pands under the action of heat, produced by a fire for instance, it will pass up the bore 2 and then flow through the hole 4 into the grooves l. Thus the mercury will contact the upper cap and electrically connect the caps together, thus completing the circuit, portions of which are con-- nected with the lower clamp member ID and another portion with the upper clamp member H, the clamp members being carried by the block l2 of non-conductive material and said clamp members engaging the ends of the device as shown in Figure 1.

By adjusting the lower cap 8 the level of mercury therein can be adjusted whereby the device can be adjusted to operate at any desired temperature.

It is thought from the foregoing description that the advantages and novel features of the invention will be readily apparent.

It is to be understood that changes may be made in the construction and in the combination and arrangement of the several parts, provided that such changes fall within the scope of the appended claim.

Having described the invention what is claimed as new is:

A device of the class described comprising a plug of non-conductive material and having a bore therein extending from a point spaced from its upper end through the lower end, said lower OLAF A. SAHLBOM. 

